This is how we organise our globes stock by base. We give the bases our own obvious names because frankly there doesn't seem to be a standardised worldwide system. The particular machine model number will then determine what particular voltage and wattage the globe is - i.e. within the base type classifications there are different voltages and wattages. This means that although the base may look the same different machines may have different voltages / wattages. We will make sure you get the right one if you follow our order instructions.